"Vagrant 1.0 was released in 2013 as a stable release. Vagrant 1.0 only supported VirtualBox as a provider, only supported a handful of Linux operating systems as guests, and supported a simple up/destroy workflow. Since Vagrant 1.0, we've added support for multi-providers such as VMware and Docker, guests such as Windows, macOS, and complex workflows including snapshots. These major changes are followed by hundreds of improvements and bug fixes."
I think the person you replied to was asking about major changes from the last 1.x release, to v2.0. Of which, there don't appear to be any major ones.
